Aurora shooting suspect James Holmes in court

The Century 16 Theatre where a masked gunman killed 14 people at a midnight showing of the new Batman movie in Aurora, Colorado July 20, 2012. A masked gunman killed 14 people at a midnight showing of the new Batman movie in a suburb of Denver early on Friday, sparking pandemonium when he hurled a teargas canister into the auditorium and opened fire on moviegoers.

The man accused of shooting dead 12 people in a movie theater in Aurora, Colorado, has appeared in court.

Suspect James Holmes attended the Arapahoe County Court this morning. A live broadcast showed him in prison clothes, looking dazed and occasionally frowning. His hair was dyed bright red.

Key to building the case for first-degree murder will be establishing that the attacks were premeditated. Police are collecting evidence that allegedly shows Holmes planned the attacks for months beforehand, according to The Guardian, including surveillance footage of him taking a delivery of the more than 6,000 rounds of ammunition and bulletproof clothing he bought on the Internet.

Police have also recovered the suspect's computer from his booby-trapped apartment, Agence France Presse reported, which may reveal crucial traces of forward planning.

Many people in Aurora believe the attack was calculated to win its perpetrator publicity – and have vowed not to give it to him by refusing to use his name. Colorado Governor John Hickenlooper refers to Holmes simply as "Suspect A," Reuters quoted him as saying.

President Barack Obama, who visited victims and their families in Colorado last night, also avoided speaking the suspect's name.

"In the end, after he has felt the full force of our justice system, what will be remembered are the good people who were impacted by this tragedy," Obama said.

The president's address was followed by a prayer vigil for the victims in Aurora. According to the Denver Post, thousands of people came to leave flowers, light candles, and pay their respects.